Steam and internal-combustion engine indicator.



'W. P. CLYDE.

STEAM AND INTERNAL COMBUSTION ENGINE INDICATOR.

APPLICATION FILED NOV. 9, 1914.

1,201,557. Patented Oct. 17,1916.

IIIHIII IIII" UNITED STATES PATENT OFFICE WALTER rnovAN CLYDE, or GLASGOW, SCOTLAND, AssIeNon To DOIBBIE McINNES LIMITED, or GLASGOW, SCOTLAND.

STEAM AND INTERNAL-COMBUSTION ENGINE INDICATOR.

, Specification of Letters Patent.

Patented Oct. 17, 1916.

Application filed November 9, 1914. Serial No. 871,192.

To all whom it may concern:

Be it known that I, VVALTER PROVAN CLYDE, managing director of Dobbie Mc- Innes Ltd., of 57 Bothwell street, Glasgow, Scotland, chronometer, nautical, and scientific instrument makers, have invented certain new and useful Improvements in and Connected with Steam and Internal-Combustion Engine Indicators, of which the fol lowing is a specification.

My invention which relates to steam and internal combustion engine indicators, has reference to the revolving metal arm or bracket carrying the parallel motion and pressure springs of said indicators.

According to my invention I so construct the metal arm and component parts as to make a more rigid fixing than heretofore and to prevent the cover or cap becoming loose when the piston is detached from the motion, and I place the pressure spring by disposing it between the piston and parallel motion of the indicator so that when the spring is in operation it is extended instead of being compressed.

In order that my invention may be properly understood and readily carried into effeet I have hereunto appended one sheet of drawings, of which- Figure 1 is a front elevation and part vertical section of an indicator made in accordance with and embodying my invention with the paper drum and other portions thereof removed. Fig. 2 is a plan of the same. Fig. 3 is a horizontal section taken through the upper part of the piston rod on the line a, b, of Fig. 1. Fig. at is a vertical section illustrating the disposition and connection of the pressure spring, all hereafter more fully referred to and described.

Referring to the drawings, I form on the revolving metal arm A a solid bracket C with an opening D, in which is mounted the parallel motion B, Fig. 2. The said bracket G is of semicircular formation, having its ends or extremities closed, as shown, but which may conveniently have one of its ends open. The dual pivotal connection having a large transverse area insures great stability and serves to eliminate the evil effects of strain produced principally at high pressure, and more particularly with internal combustion engines on the parallel motion B with consequent friction thereby vitiating the accuracy of the instrument as experienced in the present form of a single overhung bracket.

Owing to the construction of the bracket 0, the cover G which holds the base of the bracket C in position, while loose and easily accessible for adjusting purposes is prevented from falling out when the cylinder cover G, and piston rod E, are unscrewed for the purpose of changing the spring F. The lower end of the said pressure spring F is connected to the cover or lid G connected to the top of the cylinder H by means of inserting the lower coils thereof through lugs or radial projections I, or into a solid metal cap and is therefore held rigid or stationary at that point, as if integral with the cylinder casing, while the upper end of the said spring F is connected by flanged and screw attachment or both to an upper part of the piston rod E, and moves with it, by similar lugs or radial projections I The thrust or upward movement of the'piston J overcomes the power of the spring F and doing so extends its length vertically as opposed to indicators presently in use which are compressed by the upstroke of the piston.

It will be seen that the bracket K which carries the cylinder lies well to the back of the indicator. This arrangement gives free access to the pressure spring and facilitates the unscrewing of the cylinder lid or cover G.

I claim:

An engine indicator, comprising a cylinder, a rod, movable longitudinal within said cylinder, a parallel motion, connected intermediate its two extremities, to the upper end of the rod, a bracket, having both of its ends secured to the upper end of the cylinder, extending above the same, and being provided with an opening directly above the upper end of the rod, one end of said parallel motion being secured to the bracket in the opening therein.

In testimony whereof I affix my signature in presence of two witnesses.

WALTER PROVAN CLYDE.

Witnesses:

JOHN LIDDLE, JOHN TRAIN LIDDLE.

Copies of this patent may be obtained tor five cents each, by addressing the "Sommissioner 02 22mm, Washington, D. G. 

